[mir] Minor doc fix

This removes trailing whitespace and adds a missing article.

ONE-DCO-1.0-Signed-off-by: Piotr Fusik <p.fusik@samsung.com>

compiler/mir/Readme.md

@@ -21,16 +21,16 @@ special attributes specific to different operation types.
 Mir has a protobuf serializer/deserializer for shapes and tensors (see `mir.proto` schema).
 
 For list of currently supported operations, see `mir/ops/operations.lst.h`.
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+
 ### How to use
 Can be included as a `CMake` target.
 
 ### TODO
 
 * Expand serialization
 * Add More to readme 
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+
 ### Dependencies
 
-Mir depends on `adtitas` library, which provides the `small_vector` data type.
-    
+Mir depends on the `adtitas` library, which provides the `small_vector` data type.
+